1. Field of the Invention
The present invention relates to a technique for inspecting whether electronic components of an electronic apparatus are connected properly or not.
2. Description of the Related Art
Connections of electronic components of electronic apparatuses having simple configurations have been inspected by detecting a voltage applied to each electronic component (Japanese Patent Laid-Open No. 2002-286782).
However, it is difficult to inspect connections of electronic components (such as solenoids, clutches, motors, and sensors) in complicated electronic apparatuses. For example, it is becoming hard to detect an open-circuit condition caused by a disconnection of a connector or a short circuit caused by a pinched harness, making it difficult to maintain the quality of electronic apparatuses.
Furthermore, conventional methods cannot detect an imperfect connection of an electronic component such as a photo-interrupt sensor in which results of detection by detecting voltages vary depending on the conditions of objects to be detected by the sensor. To determine results of detection, as many input signal controls as the number of objects to be detected are required. Accordingly, a huge number of signals must be handled by a control LSI. Therefore, it was difficult to inspect connections of all components of an apparatus.